1. Chapter 8 Classes and Objects: A Deeper Look

2. The Time Object

3. Problem Description Time consists of hour (0 - 23), minute (0 - 59), and second (0 - 59). Develop the JTime class to represent time. JTime should have the following behaviors –Set a new time according to the new hour, minute, and second. Do not forget to validate these new values –Return a string to represent itself in the universal-time format: HH:MM:SS –Return a string to represent itself in the standard-time format: HH:MM:SS AM or PM

4. Questions 1.What is a valid hour? Minute? Second? 2.What is the universal-time format? 3.What is the standard-time format?

5. Answers 1.Valid hour: 0 - 23 Valid minute: 0 - 59 Valid second: 0 - 59 2.Universal-time format: HH:MM:SS 3.Standard-time format: H:MM:SS AM or PM –If hour is 0 or 12, H will be 12. Otherwise, H will be (hour % 12) –If hour less than 12, it’s AM. Otherwise, it’s PM

6. Class Diagram

7. Developing the Constructor Without Input Data Validation

10. Adding Input Data Validation to the Constructor

13. Setting New Time

16. Getting the Universal-Time Format

19. Getting the Standard-Time Format

22. Exercise Compare our solution with the Deitel’s solution (in the next slides)

25. The Date Object

26. Problem Description Date consists of month (1 - 12), day (1 - 31), and year. Develop the JDate class and its constructor to represent a date. Do not forget to check the validity of input data Develop the toString() method for the JDate class according to the MM/DD/YYYY format

27. Question Q: How can we know that a year is leap year? A: A year is leap year if 1)It is divisible by 400, OR 2)It is divisible by 4 but not divisible by 100

28. Class Diagram To be filled

29. Step 1. Developing Constructor Without Input Validation

32. Validating the Month

33. Validating the Day

34. The Employee Object

35. Problem Description Info of an employee includes: First name, last name, birth date, and hire date. Develop the Employee class

36. Example First name: Sue Last name: Jones Birthday: Sept 5, 1986 Hire date: Jan 1, 2007

37. Class Diagram

41. A Better Design

42. An Even Better Design

46. Drawing Random Lines

47. Problem Draw a random number of lines (at least 1 and at most 5) inside a frame

50. Exercise Exercise 8.6

51. The Stock Problem A company’s stock consists of –The trading symbol. A short series of characters that are used to identify the stock on the stock exchange –The current price per share of the stock A stock purchase has the following information –The stock that was purchased –The number of shares Calculate the cost of the purchase

52. The Course Problem A course holds the following information: –The course name –The instructor’s last name, first name, and office number –The textbook’s title, author, and publisher

53. The Sports Car Problem A sports car has the following information: –The type (make) –The color –The price The type is either Porsche, Ferrari, or Jaguar The color is either red, black, blue, or silver

54. The Retail Problem An item in a retail store holds the following information –A brief description of the item –The number of units currently in inventory –The item’s retail price For example DescriptionUnits on HandPrice Item #1Jacket1259.95 Item #2Designer Jeans4034.95 Item #3Shirt2024.95

55. A cash register is a sale of a retail item Given the quantity of items being purchased, the cash register provides the sale’s subtotal, amount of sales tax, and total –The subtotal is the quantity multiplied by the price –The sales tax rate is 6% of a retail sale –The total is the subtotal plus the sales tax

56. The Parking Problem This problem is about a police officer issuing a parking ticket A parked car holds the following information –The car’s make (for example Toyota) –The model (for example, Nissan Z28) –The color –The license number (for example XY-1234) –The number of minutes that the car has been parked A parking meter records the number of minutes of parking time that has been purchased A parking ticket is responsible for –Reporting the make, model, color, and license number of the illegally parked car –Reporting the amount of the fine, which is $25 for the first hour or part of an hour that the car is illegally parked, plus $10 for every additional hour or part of an hour that the car is illegally parked –Reporting the name and badge number of the police officer issuing the ticket A police officer inspecting parked cars is responsible for –Telling his/her name and badge number –Examining the parked car and the parking meter, and determining whether the car’s time has expired –Issuing a parking ticket if the car’s time has expired